Effect of the duration of composting on the amount of compost produced and the yield of mushrooms

Prolonging duration of composting, especially of Stage II (peak-heating), increased loss of material, reduced bulk density and resulted in a lower weight of compost prepared per tonne of original straw,Yield of mushrooms (Agaricus bisporus) per tonne of prepared compost was unaffected by prolonging Stage II, but was reduced when expressed per unit area, per tonne of compost filled, or per tonne of original straw, because of loss of materials and reduced bulk density.Fruit bodies of a weed mould, Coprinus sp., were more numerous during mushroom cropping on composts which had been prepared with the shortest Stage II, but there was no correlation between occurrence of Coprinus sp. and the yield of mushrooms per tonne of prepared compost.A basis is proposed for comparing composts prepared by a wide variety of methods.